Menstruation occurs mainly because shed when fertilisation doesn't occur
Question
Menstruation occurs mainly because shed when fertilisation doesn't occur
the thickened uterine lining, prepared to nourish a possible embryo, breaks down and is
the ovaries stop producing eggs permanently
the placenta detaches from a healthy pregnancy
the vagina produces excess mucus for no reason
Answer
the thickened uterine lining, prepared to nourish a possible embryo, breaks down and is
Detailed Explanation
Each month the uterine lining thickens to potentially nourish an embryo; if fertilisation doesn't occur, this lining breaks down and is shed as menstrual blood and mucus.